1. Field of the Invention
The field of this invention is core body energy regulation.
2. Background of the Invention
Instances exist where it is desired to extract thermal energy or heat from the body core of a mammal. For example, there are many instances in which it is desired to lower the internal body temperature of a subject. Instances where it is desired to extract heat from the body core of a subject include the treatment of hyperthermia, including self-induced hyperthermia resulting from work or exercise, and the treatment of temperature sensitive disorders, such as multiple sclerosis. For example, personal cooling systems are employed to alleviate symptoms of multiple sclerosis. In such methods, a patient wears a personal cooling system, e.g. a cooling helmet or garment, for a certain period of time during the day to alleviate symptoms.
While a number of different methodologies and devices have been developed for use in reducing the core body temperature of a subject, there continues to be a need for the development of new devices and protocols. Of particular interest would be the development of a device and protocol that provided for efficient heat extraction from the body core in a non-invasive manner that would be readily used by subjects, i.e. enjoy high patient compliance.
3. Relevant Literature
U.S. Pat. No. 5,683,438. See also WO 98/40039. Also of interest are: Soreide et al., xe2x80x9cA non-invasive means to effectively restore nonnothermia in cold stressed individuals: a preliminary report,xe2x80x9d J Emerg. Med. (1999 July-August)17(4):725-30 and Grahn et al., xe2x80x9cRecovery from mild hypothermia can be accelerated by mechanically distending blood vessels in the hand,xe2x80x9d J. Appl Physiol. (1998) 85(5):1643-8. See also: Ku et al., Am. J. Phys. Med Rehabil. (September-October 1999) 78:447-456; Ku et al., Am. J. Phys. Med. Rehabil. (November-December 1996) 75:443-450; Capello et al., Ital. J. Neurol Sci. (1995) 16: 533-539; Brown and Williams, Aviat. Space Environ Med. (1982) 53:583-586; Gordon et al., Med. Sci. Sports Exerc. (1990) 22:245-249; Watanuki, Ann. Physiol. Anthropol. (1993) 12:327-333; and Katsuura et al., Appl. Human Sci. (1996) 15:67-74. See also: Bruck K, Olschewski H. Body temperature related factors diminishing the drive to exercise. Can J Physiol Pharmacol. 1987 June;65(6):1274-80; Schmidt V, Bruck K. Effect of a precooling maneuver on body temperature and exercise performance. J Appl Physiol. 1981 April;50(4):772-8; Hessemer V, Langusch D, Bruck L K, Bodeker R H, Breidenbach T. Effect of slightly lowered body temperatures on endurance performance in humans. J Appl Physiol. 1984 December;57(6):1731-7; Olschewski H, Bruck K. Thermoregulatory, cardiovascular, and muscular factors related to exercise after precooling. J Appl Physiol. 1988 February;64(2):803-11; Booth J, Marino F, Ward J J. Improved running performance in hot humid conditions following whole body precooling. Med Sci Sports Exerc. 1997 July;29(7):943-9; Greenhaff P L, Clough P J. Predictors of sweat loss in man during prolonged exercise. Eur J Appl Physiol. 1989;58(4):348-52; Leweke F, Bruck K, Olschewski H. Temperature effects on ventilatory rate, heart rate, and preferred pedal rate during cycle ergometry. J Appl Physiol. 1995 September;79(3):781-5; Lee D T, Haymes E M. Exercise duration and thermoregulatory responses after whole body precooling. J Appl Physiol. 1995 December;79(6):1971-6; Marsh D, Sleivert G. Effect of precooling on high intensity cycling performance. Br J Sports Med. 1999 December;33(6):393-7; and Gonzalez-Alonso J, Teller C, Andersen S L, Jensen F B, Hyldig T, Nielsen B. Influence of body temperature on the development of fatigue during prolonged exercise in the heat. J Appl Physiol. 1999 March;86(3): 1032-9.
Methods and devices for extracting thermal energy from the body core of a mammal are provided. In practicing the subject methods, a portion of the mammal, e.g. a limb or portion thereof, is placed in a sealed enclosure to produce an enclosed portion of the mammal. A surface of the enclosed portion of the mammal is then contacted with a low temperature medium under negative pressure conditions for a period of time sufficient to extract the desired amount of heat from the body core of the mammal. The subject methods and devices find use in a variety of applications, e.g. providing relief from temperature sensitive disorders, such as multiple sclerosis, and the treatment of hyperthermia.
The subject methods are particularly suited for use in enhancing the physical ability of a mammal. In these embodiments, thermal energy is extracted from the core body of the mammal during the physical procedure for a period of time sufficient to enhance the ability of the mammal to perform the physical procedure. To extract thermal energy from the core body of the mammal in the subject methods, a portion of the mammal, e.g., a limb or portion thereof, is placed in a sealed enclosure to produce an enclosed portion of the mammal. A surface of the enclosed portion of the mammal is then contacted with a low temperature medium under negative pressure conditions for a period of time sufficient to provide for the requisite core body thermal energy extraction. The subject methods and devices find use in the enhancement of the ability of a mammal to perform a variety of different physical procedures, including athletic procedures.